Collaborative Research: ETBC--Exploring Forest Ecosystem Response to Water Availability and the Impact on Biogeochemical and Water Cycles

该研究旨在确定和量化可作为云核的气溶胶的生物发生与通过改变降水模式对产生更多气溶胶的植被过程的反馈之间的联系。该方法结合了实验、实地测量和实验室调查。每一个都代表了整个循环的关键组成部分：1)沿着美国西南部广泛的样带调查生物挥发性有机化合物的重要来源；2)生物气溶胶颗粒的大气调查，将在其中一个地点进行，包括对颗粒进行DNA测序以确定其来源的有趣想法；3)进行两项实地研究，以操纵水分并调查对植被的影响，其中一项涉及对单株黄松施加干旱并调查其VOC排放，另一项涉及在单独（但附近）的一组地块上施加不同的湿度制度，以量化湿度对土壤/凋落物VOC排放的影响；4)生物成因冰核和云凝结核的研究。这四项调查将在涉及一个模型的第五项活动中联系在一起：自然气体和气溶胶排放模型（MEGAN）。这项工作的一个主要的更广泛的影响将是通过改善一个地表-大气耦合模型来实现的，该模型可以从国家大气研究中心（NCAR）的网站上向更广泛的科学界提供，并且能够支持未来涉及植物-云相互作用的研究。该项目还将通过让至少6名代表性不足的本科生参与研究项目，支持NCAR和科罗拉多大学的科学计划的多样性。为了将项目的影响扩大到公共部门和K-12社区，将开发基于网络的教育材料，解释气候变化对森林生态系统的影响，并将包括来自马尼托森林观测站的实时数据。最终，这些结果将导致评估美国西部区域气候变化对生态系统影响的新策略，并通过认识生态系统在放大或抑制进一步气候变化中所起的作用来管理这些影响。

The study aims to identify and quantify linkages between the biogenesis of aerosols that can function as cloud nuclei and the feedback through altered precipitation patterns on vegetation processes that generate more aerosols. The approach combines experiments, field measurements and laboratory investigations. Each represents a key component of the overall cycle: 1) surveys of important sources of biogenic volatile organic compounds along a broad transect of sites in the Southwestern U.S.; 2) atmospheric surveys of biological aerosol particles, which will take place at one of the sites and include the interesting idea of DNA sequencing of particles to identify their sources; 3) two field studies to manipulate water and investigate impacts on vegetation, one involving imposition of drought in individual ponderosa pine trees and an investigation of their VOC emissions and the other on a separate (but nearby) set of plots to impose different moisture regimes to quantify the impact of moisture on soil/litter VOC emissions; 4) studies of biogenic ice nuclei and cloud condensation nuclei. These four investigations will be linked together in a fifth activity involving a model: Model of Emissions of Gases and Aerosols from Nature (MEGAN).One of the principal broader impacts of this work will occur through the improvement of a coupled surface-atmosphere model that is available to the broader scientific community from the National Center for Atmospheric Research (NCAR) web site, and is capable of supporting future studies involving plant-cloud interactions. The project will also support diversity in science initiatives at NCAR and the University of Colorado by involving at least six underrepresented-group undergraduate students in the research project. To extend the impact of project into the public sector and the K-12 community, web-based educational materials will be developed that will explain the impact of climate change on the forest ecosystem, and will include real-time data from the Manitou Forest Observatory. Ultimately, the results will lead to new strategies for assessing the impact of regional climate change on ecosystems in the Western U.S. and managing those impacts through recognition of the role ecosystems play in amplifying or dampening further climate change.